This invention relates to game balls, particularly golf balls, and the method of manufacturing the same. More particularly, this invention relates to a ball having a liquid core of decreased compressability.
Although this invention finds particular utility in golf balls, the invention is applicable to any liquid center game ball where it is necessary or desirable to vary the degree of compressability of the center.
Liquid center golf balls today are produced by providing a body of liquid in a spherical envelope as the core or center about which thread or other wrappings are disposed. The wound body is then enclosed in a dimpled Balata or Surlyn cover. Various liquid materials have been used in the centers, for example water, liquid glue, paste and honey. Indeed, other materials have also been used, for example steel ball bearings, steel pellets, and oil-filled capsules.
Liquid has been considered one of the better, if not the best, materials for the center of a golf ball because liquid is known to be essentially non-compressable. A center which exhibits a decreased degree of compressability increases the immediacy of the transmittal of force of a golf club head striking the ball back to the club face. That force first compresses the ball against the club face and then causes the ball to rebound off of the club face resulting in an increase in accelleration away from the club face. That also results in a pleasing "click" and feel. The increase in acceleration provides a means to attain maximum velocity in a shorter period of time.
There have been a number of attempts at varying the compressability of a golf ball. For example, U.S. Pat. No. 2,074,808 to Rickey discloses a method of permeating a liquid core with a gaseous material, such as dry ice. The liquid core is frozen which causes the core to contract. Rickey teaches that if the ball is wound while the core is frozen, after the ball "thaws out" the core will expand, the gaseous material will evaporate, and the tensions on the windings will increase thereby rendering the ball harder than what could be effected by tensioning the winding alone.
Others have offered other designs. For example, U.S. Pat. No. 2,264,604 to Young discloses a ball using a solid pellet as the core. But in order to center the pellet in the center of the golf ball, Young first embeds the pellet in dry ice or some other readily liquifiable or gasifiable substance. When the core "thaws out", the gas escapes and the windings are said to force the pellet to the center of the ball.
Despite numerous attempts and years of varying designs, there have been very few, if any, successful solutions to the problem of varying the compressability of liquid center balls.